Biologically implantable prosthesis and methods of using the same

ABSTRACT

A biologically implantable prosthesis is disclosed. The prosthesis can have a circumferentially expandable wall and elements that prevent the wall from collapsing once the wall is expanded. Methods of making and using the prosthesis are also disclosed.

BACKGROUND OF THE INVENTION

[0001] 1. Field of the Invention

[0002] The present invention relates generally to a biologicallyimplantable prosthesis, a heart valve assembly using the prosthesis, andmethods of using the same within an annulus of the body.

[0003] 2. Description of the Related Art

[0004] Prosthetic heart valves can replace defective human valves inpatients. Prosthetic valves commonly include sewing rings or suturecuffs that are attached to and extend around the outer circumference ofthe prosthetic valve orifice.

[0005] In a typical prosthetic valve implantation procedure, the heartis incised and the defective valve is removed leaving a surrounding areaof locally tougher tissue. Known heart valve replacement techniquesinclude individually passing sutures through the tough tissue to form anarray of sutures. Free ends of the sutures are extended out of thethoracic cavity and laid, spaced apart, on the patient's body. The freeends of the sutures are then individually threaded through an edgearound the circumference of the sewing ring. Once all sutures have beenrun through the ring, all the sutures are pulled up taught and theprosthetic valve is slid or “parachuted” down into place adjacent thetough tissue. Thereafter, the prosthetic valve is secured in place bytraditional knot tying with the sutures.

[0006] The sewing ring is often made of a biocompatible fabric throughwhich a needle and suture can pass. The prosthetic valves are typicallysutured to a biological mass or annulus that is left when the surgeonremoves the existing valve from the patient's heart. The sutures aretied snugly, thereby securing the sewing ring to the annulus and, inturn, the prosthetic valve to the heart.

[0007] Sewing rings can be tedious to secure to the valve orifice.Further, attaching the sewing ring to the annulus can be time consumingand cumbersome. The complexity of suturing provides a greateropportunity for mistakes and requires a patient to be on cardiopulmonarybypass for a lengthy period. It is also desirable to provide as large ofa lumen through the prosthetic valve as possible to improvehemodynamics. However, techniques for attaching the sewing ring to theorifice typically require the area of the valve lumen be reduced toaccommodate an attachment mechanism. For example, the sewing ring istypically retained on top of the annulus, resulting in a lumen that is,at the largest, the size of the original lumen.

[0008] A patient can also have a natural valve lumen that isdetrimentally small. In these cases, the natural valve can be gussetedbefore the prosthetic valve is implanted. To gusset the natural valve, alongitudinal incision can be made along the wall of the lumen. The lumencan then be circumferentially expanded and the now-expanded incision canbe covered with a patch graft or other membrane and stitched closed.

[0009] U.S. Pat. No, 4,743,253 to Magladry discloses a suture ring witha continuous compression ring. Magladry's ring is ductile, but providesa compressive, not expansive, force. In fact, the ring taught byMagladry is intended for placement over a heart valve and providescompression on the heart valve.

[0010] U.S. Pat. No. 6,217,610 to Carpentier et al. discloses anexpandable annuloplasty ring. Carpentier et al. teach expanding the ringover the life of a patient by increasing the size of the ring by balloondilatation. The ring is intended to remodel the shape of the valveannulus, not serve as a foundation to attach a second prosthesis andform a heart valve.

[0011] U.S. Pat. No. 5,984,959 to Robertson et al. discloses anexpandable heart valve ring for attaching a synthetic valve thereto anda tool for attaching the ring to the synthetic valve. Robertson et al.teach the ring as having tabs that are used to attach to the secondprosthesis by using a second device to engage the tabs.

[0012] There is a need for a circumferentially expandablebio-prosthesis. There is also a need for a prosthesis and method thatcan expand an annulus and maintain an enlarged annulus circumference.Furthermore, there is a need for a minimally invasive heart valvereplacement procedure. Also, there is a need for a prosthesis that canprovide for the above and engagement with a second prosthesis, forexample, the crown of a heart valve. Furthermore, there is a need forthe above prosthesis that can self-engage a second prosthesis to improveimplantation time.

BRIEF SUMMARY OF THE INVENTION

[0013] One embodiment of the disclosed prosthesis is a biologicallyimplantable first prosthesis for a heart valve having acircumferentially expandable wall. The wall has a latitudinalcross-section perpendicular to the longitudinal axis, and a longitudinalcross-section parallel to the longitudinal axis. The prosthesis also hasan engagement element configured to self-engage a second prosthesis.

[0014] The first prosthesis can also have a stop, where the stopprevents the wall from circumferentially decreasing. The firstprosthesis can also have a fixturing device connector. The wall can alsobe corrugated. The wall can also have a turned lip on its leading edge.The first prosthesis can also be in an assembly where the firstprosthesis can receive a second prosthesis, for example a crown.

[0015] Another embodiment of the prosthesis is a biologicallyimplantable first prosthesis for a heart valve having a wall with afirst edge and a second edge. The wall has a longitudinal axis at thecenter of the first prosthesis, and the first edge has an engagementelement for engaging a second prosthesis. The engagement element is alsoturned toward the second edge.

[0016] The engagement element can be curved toward the second edge. Thefirst edge can be the leading edge. The first prosthesis can also have afixturing device connector that can be a port in the wall. The wall canalso be corrugated. The first prosthesis can also be in an assembly witha second prosthesis connected to the engagement element. The secondprosthesis can be a crown.

[0017] An embodiment of a method of implanting a heart valve in a valveannulus is attaching a first prosthesis to the valve annulus andattaching a second prosthesis to the first prosthesis. The firstprosthesis has a circumferentially expandable wall. The wall has alongitudinal axis, and the wall has a latitudinal cross-sectionperpendicular to the longitudinal axis.

[0018] The first prosthesis can be a ring. The second prosthesis can bea crown. The wall of the first prosthesis can have a first terminal endand a second terminal end. Attaching the first prosthesis can includefixing the first prosthesis to a biological mass with a fixturingdevice. Attaching the first prosthesis can also include snap-fitting thesecond prosthesis to the first prosthesis.

[0019] Another embodiment of a method of implanting a heart valve in avalve annulus includes attaching a first prosthesis to the valve annulusand attaching a second prosthesis to the first prosthesis. The firstprosthesis has a wall having a first edge and a second edge. The wallalso has a longitudinal axis. The first edge comprises an engagementelement, and the engagement element is turned toward the second edge.

[0020] The engagement element can be turned away from the longitudinalaxis. The first prosthesis can be a ring. The second prosthesis can be acrown. Attaching the crown can include snap-fitting the crown to thefirst prosthesis.

[0021] An embodiment of a method of increasing and maintaining the sizeof a biological valve annulus includes placing a circumferentiallyexpandable first prosthesis in the annulus. The method also includescircumferentially expanding the first prosthesis, and circumferentiallylocking the first prosthesis.

[0022] Circumferentially expanding the first prosthesis can includeincreasing the radius of the annulus from about 0.1 mm (0.004 in.) tomore than about 2.0 mm (0.08 in.). The first prosthesis can also have anengagement element configured to receive a second prosthesis.

BRIEF DESCRIPTION OF THE DRAWINGS

[0023]FIG. 1 is a bottom view of an embodiment of the prosthesis.

[0024]FIG. 2 is a top perspective view of the embodiment of theprosthesis of FIG. 1.

[0025]FIG. 3 is a bottom view of another embodiment of the prosthesis.

[0026]FIG. 4 is a top perspective view of the embodiment of theprosthesis of FIG. 3.

[0027]FIG. 5 is a bottom view of another embodiment of the prosthesis.

[0028]FIG. 6 is a top perspective view of the embodiment of theprosthesis of FIG. 5.

[0029]FIG. 7 is a bottom view of another embodiment of the prosthesiswith cut-away views of the collars.

[0030]FIG. 8 is a top perspective view of the embodiment of theprosthesis of FIG. 7 with cut-away views of the collars.

[0031]FIG. 9 is a bottom view of another embodiment of the prosthesiswith cut-away views of the collars.

[0032]FIG. 10 is a top perspective view of the embodiment of theprosthesis of FIG. 8 with cut-away views of the collars.

[0033]FIG. 11 is a top perspective view of another embodiment of theprosthesis with magnets.

[0034]FIG. 12 illustrates cross-section A-A of FIG. 11.

[0035]FIG. 13 is a top perspective view of another embodiment of theprosthesis with magnets.

[0036]FIG. 14 illustrates cross-section B-B of FIG. 13.

[0037]FIG. 15 is a top perspective view of another embodiment of theprosthesis with magnets.

[0038] FIGS. 16-18 are top views of various deformable embodiments ofthe prosthesis in unexpanded states.

[0039]FIG. 19 is a top view of the embodiment of the prosthesis of FIG.12 in an expanded state.

[0040] FIGS. 20-22 illustrate various embodiments of the fixturingdevice connectors.

[0041] FIGS. 23-25 illustrate various embodiments of the receivingelements.

[0042]FIGS. 26 and 27 are cut-away views of various embodiments of thereceiving elements.

[0043] FIGS. 28-33 illustrate various embodiments of the protrusions.

[0044]FIG. 34 illustrates the steering elements.

[0045] FIGS. 35-43 are cross-sections of various embodiments of the wallof the prosthesis.

[0046]FIG. 44 illustrates an embodiment of the prosthesis of FIG. 38.

[0047]FIGS. 45 and 46 illustrate cross-sections of the wall of theprosthesis with various embodiments of the covering.

[0048] FIGS. 47-52 illustrate various embodiments of the engagementelement.

[0049]FIG. 53 is a cut-away view of an embodiment of positioning theprosthesis in an annulus with a solid view of the prosthesis.

[0050]FIG. 54 is a cut-away view of an embodiment of positioning theprosthesis in an annulus.

[0051]FIGS. 55 and 56 illustrate various embodiments of the protrusionsand receiving elements when the prosthesis is not expanded.

[0052]FIG. 57 is a cut-away view of an embodiment of expanding theprosthesis.

[0053]FIGS. 58 and 59 illustrate an embodiment of an expansion tool.

[0054]FIGS. 60 and 61 illustrate another embodiment of an expansiontool.

[0055]FIGS. 62 and 63 illustrate various embodiments of the protrusionsand receiving elements when the prosthesis is expanded.

[0056]FIG. 64 is a cut-away view of fixturing the prosthesis to abiological mass.

[0057] FIGS. 65-68 illustrate an embodiment of a method and assembly forfixturing the prosthesis to a biological mass.

[0058]FIG. 69 is a cut-away view of positioning the second prosthesisonto the first prosthesis with a solid view of the second prosthesis.

[0059]FIG. 70 is a cut-away view of attaching the second prosthesis tothe first prosthesis.

[0060] FIGS. 71-77 are exploded views of various embodiments ofattaching the second prosthesis to the first prosthesis.

[0061]FIG. 78 is an exploded view of an embodiment of attaching thesecond prosthesis to an adapter and attaching the adapter to the firstprosthesis.

[0062]FIGS. 79 and 80 illustrate cross-sections C-C and D-D,respectively, from FIG. 78.

[0063]FIG. 81 is a top view of an embodiment of the first prosthesiswith the second prosthesis attached thereto.

[0064] FIGS. 82-84 illustrate an embodiment of a method of removing thesecond prosthesis from the first prosthesis.

DETAILED DESCRIPTION

[0065]FIGS. 1 and 2 illustrate an embodiment of a biologicallyimplantable first prosthesis 2. The first prosthesis 2 can have a wall4. The wall 4 can have material strength and dimensions known to onehaving ordinary skill in the art to make the first prosthesisresiliently expandable. The wall 4 can have an open form or spirallongitudinal cross-section, as shown in FIG. 1. The longitudinalcross-section can be perpendicular to a central longitudinal axis 6.

[0066] The wall 4 can have a first terminal end 8 and a second terminalend 10. Each end 8 and 10 can be defined from a midpoint 12 of the wall4 to a first terminus 14 or a second terminus 16 of the wall 4 at therespective end 8 or 10. The wall 4 can have an end difference length 18.The end difference length 18 can be the shortest angular length from thefirst terminus 14 to the second terminus 16. The wall 4 can also have aleading edge 20 and a trailing edge 22. The leading edge 20 and trailingedge 22 can be substantially perpendicular to the longitudinal axis 6.The first prosthesis 2 can have a circumference equivalent to a walllength 24 minus an end difference length 18. The wall 4 can have a wallheight 25. The wall height can be from about 3.18 mm (0.125 in.) toabout 12.7 mm 8.26 mm (0.500 in.), for example about (0.325 in.). Thewall 4 can also be void of any attachment device with which to fix oneend 8 or 10 of the wall 4 to the other end 8 or 10 of the wall 4. Thewall 4 can made from stainless steel alloys, nickel titanium alloys(e.g., Nitinol), cobalt-chrome alloys (e.g., ELGILOY® from ElginSpecialty Metals, Elgin, Ill.; CONICHROME® from Carpenter Metals Corp.,Wyomissing, Pa.), polymers such as polyester (e.g., DACRON® from E. I.Du Pont de Nemours and Company, Wilmington, Del.), polypropylene,polytetrafluoroethylene (PTFE), expanded PTFE (ePTFE), polyether etherketone (PEEK), nylon, extruded collagen, silicone, radiopaque materialsor combinations thereof. Examples of radiopaque materials are barium,sulfate, titanium, stainless steel, nickel-titanium alloys and gold.

[0067]FIGS. 3 and 4 illustrate an embodiment of the first prosthesis 2that can be mechanically expandable. A first protrusion 26 and a secondprotrusion 28 at the first terminal end 8 can extend from the wall 4.The protrusions 26 and 28 can extend perpendicular to the wall 4 orperpendicular to the longitudinal axis 6. The protrusions 26 and 28 canbe tabs, brads, extensions, balls, rods or a combination thereof. Theprotrusions can have a protrusion depth 30 sufficient to retain the wall4.

[0068] The wall 4 can also have a first receiving element 32 and asecond receiving element 34 at the second terminal end 10 that receiveor engage the first protrusion 26 and the second protrusion 28,respectively. The wall 4 can also have more or less (e.g., one or zero)receiving elements 32 or 34. The receiving elements 32 and 34 can beholes in the wall 4. The receiving elements 32 and 34 can also bedivets, dimples, hooks, slots, or a combination thereof. The protrusions26 and 28 and receiving elements 32 and 34 can act together as a stop,or an interference fit, to prevent the first prosthesis 2 fromcircumferentially extending or decreasing beyond desired limits.

[0069]FIGS. 5 and 6 illustrate an embodiment of the first prosthesis 2that can have protrusions 26 and receiving elements 32 that can bedimples. The protrusions 26 and receiving elements 32 can be in a firstrow 36, a second row 38, and additional rows 40. The protrusions 26 canalso be in a first column 42, a second column 44, and additional columns46. The receiving elements 32 can have a receiving element depth 46within the same range of sizes as the protrusion depth 36, above.

[0070]FIGS. 7 and 8 illustrate an embodiment of the first prosthesis 2that can have the protrusions 26 and 28 extending from the firstterminus 14 substantially at a tangent to the wall 4. The protrusions 26and 28 can be rods 48 with balls 50 at the ends of the rods 48. Thereceiving elements 32 and 34 can extend from the second terminus 16substantially at a tangent to the wall 4. The receiving elements 32 and34 can be collars 52 for receiving the balls 50. The wall 4 can have alongitudinal cross-section in the shape of a circular open curve, asshown in FIG. 7. A circumferential gap 54 can exist between the firstterminus 14 and the second terminus 16.

[0071]FIGS. 9 and 10 illustrate an embodiment of the first prosthesis 2that can have different embodiments of protrusions 26 and 28 andreceiving elements 32 and 34. The first prosthesis 2 of FIGS. 9 and 10can also have a wall angle 56 relative to the longitudinal axis 6controlled by the dimensions of the protrusions 26 and 28 and receivingelements 32 and 34 and the locations of the protrusions 26 and 28 andreceiving elements 32 and 34 on the wall 4. The wall angle 56 can befrom about 10° to about 60°, more narrowly from about 20° to about 45°,for example about 25°. The protrusions 26 and 28 and the receivingelements 32 and 34 can be located along the trailing edge 22, theleading edge 20 or therebetween.

[0072]FIGS. 11 and 12 illustrate an embodiment of the first prosthesis 2with the wall 4 having a bottom segment 58 and a top segment 60. Thefirst prosthesis 2 can be deformably circumferentially expandable. Thebottom segment 58 can have the wall angle 56 relative to thelongitudinal axis 6. The angle between the bottom segment 58 and the topsegment 60 can be a joint angle 62. The joint angle 62 can be from about90° to about 180°, more narrowly from about 90° to about 160°, forexample about 120°. The wall 4 can also have a first steering groove 64that can extend over the length of the bottom segment 58. The wall 4 canalso have a second steering groove 66 that can extend over a portion ofthe length of the bottom segment 58. The grooves 64 and 66 can helpangularly align, with respect to the longitudinal axis 6, a secondprosthesis 68 that can be attached to the first prosthesis 2. Thegrooves 64 and 66 can also prevent the rotation of the first prosthesis2 with respect to the second prosthesis 68. The second groove 66 canalso help to longitudinally align the second prosthesis 68.

[0073] The first prosthesis 2 can also have engagement elements, forexample top magnets 70 in the top segment 60 and bottom magnets 72 inthe bottom segment 58. The magnets 70 and 72 can have a magnet height74, a magnet width 76 and a magnet length 78. The magnets 70 and 72 canbe rare earth, high strength-type magnets. The magnets can be made fromneodymium-iron-boron and can be encapsulated in a coating made from PTFE(e.g., TEFLON® (from E. I. Du Pont de Nemours and Company, Wilmington,Del.), PEEK, a similarly inert and stable biocompatible polymer, or acombination thereof. A radiopaque material can also be added to thecoating. The top and/or bottom magnets 70 and/or 72 can be customized toallow for only one angular orientation of the second prosthesis 68 bychanging the polarity of one or an irregular number of magnets 70 and/or72 (e.g., positive) to be different from the polarity of the remainingmagnets 70 and/or 72 (e.g., negative).

[0074] In one example, 24 magnets 70 can be evenly distributed aroundthe circumference of the first prosthesis 2. The magnet heights 74 canbe about 3.175 mm (0.125 in.). The magnet widths 76 can be about 3.175mm (0.125 in.). The magnet lengths 78 can be about 1.59 mm (0.0625 in.).

[0075]FIGS. 13 and 14 illustrate an embodiment of the first prosthesis 2similar to the embodiment illustrated in FIGS. 11 and 12. The presentembodiment of the first prosthesis 2 can have a cloth sewing surface 80.The magnets 70 can be square or rectangular in cross-section (as shownin FIGS. 11 and 12) or oval or circular in cross-section (as shown inFIGS. 13 and 14). The wall 4 can also be multiple segments 58 and 60, asshown in FIGS. 11 and 12, or a single segment, as shown in FIGS. 13 and14.

[0076]FIG. 15 illustrates an embodiment of the first prosthesis 2similar to the embodiment illustrates in FIGS. 11 and 12. The firstprosthesis 2 in the present embodiment can also be mechanically and/orresiliently circumferentially expandable.

[0077] FIGS. 16-18 illustrate deformable embodiments of the firstprosthesis 2. In an unexpanded state, the first prosthesis 2 can have anunexpanded diameter 82. The embodiment of the first prosthesis 2 in FIG.16 can have a smooth wall 4, thereby relying on hoop strain to expand.In FIG. 17, the embodiment can have an accordianed wall 4 with multiplepleats or folds 84. The folds 84 can open or unfold to maximizecircumferential expansion of the wall 4 during use. The embodiment ofthe first prosthesis 2 in FIG. 18 can have a single large fold 84 forthe same purpose as the folds 84 shown in FIG. 17. FIG. 19 illustrates adeformable embodiment of the first prosthesis 2 in an expanded state. Aradial force, as shown by arrows, directed away from the longitudinalaxis 6 can expand the first prosthesis 2 to an expanded diameter 86.Materials and dimensions of the first prosthesis 2 can be selected byone having ordinary skill in the art to permit the ratio of theunexpanded diameter 82 to the expanded diameter 86 to be from about 0%to about 50%, more narrowly from about 5% to about 20%, yet morenarrowly from about 9% to about 12%, for example about 9.5%.

[0078]FIG. 20 illustrates a length of the wall 4 that can have a firstfixturing device connector 88 and a second fixturing device connector90. The fixturing device connectors 88 and 90 can be ports or holes inthe wall 4. The fixturing device connectors 88 and 90 can be ovular andcan have a fixturing device connector height 92 and a fixturing deviceconnector length 94. The fixturing device connector height 92 can befrom about 0.51 mm (0.020 in.) to about 3.18 mm (0.125 in.), morenarrowly from about 1.0 mm (0.040 in.) to about 1.5 mm (0.060 in.), forexample about 1.3 mm (0.050 in).

[0079]FIG. 21 illustrates a length of the wall 4 that can have first,second, and additional fixturing device connectors 88, 90 and 96. Thefixturing device connectors 88, 90 and 96 can be circular in shape. FIG.22 illustrates a length of the wall 4 that can have the fixturing deviceconnectors 88, 90 and 96 attached to the leading and trailing edges 20and 22. The fixturing device connectors 88, 90 and 96 can be made fromfabric or metal, for example polymers such as polyester (e.g., DACRON®from E. I. Du Pont de Nemours and Company, Wilmington, Del.),polypropylene, PTFE, ePTFE, nylon, extruded collagen, silicone,stainless steel alloys, nickel-titanium alloys (e.g., Nitinol),cobalt-chrome alloys (e.g., ELGILOY® from Elgin Specialty Metals, Elgin,Ill., CONICHROME® from Carpenter Metals Corp., Wyomissing, Pa.) orcombinations thereof. Variously shaped and configured fixturing deviceconnectors 88, 90 and 96 can be on the same wall 4.

[0080]FIG. 23 illustrates a length of the wall 4 that can have thereceiving elements 32 and 34. The receiving elements 32 and 34 can beports or holes in the wall 4. The receiving elements 32 and 34 and thefixturing device connectors 88, 90 and 96 can be the same element. Thereceiving elements 32 and 34 can have a first setting position 98 and afirst neck 100 at one end of the first setting position 98. The firstsetting position 98 can have a setting position length 102 from about 4mm (0.2 in.) to about 10 mm (0.4 in.), for example about 6.3 mm (0.25in.). The first neck 100 can have a neck width 104. The first neck 100can be at a first end of a second setting position 106. The receivingelements 32 and 34 can have more or less than two setting positions 98and 106 (e.g., one or zero). At a second end of the second settingposition 106, the second setting position 106 can have a second neck108. The second neck 108 can be at a first end of a final stop position110. The final stop position 110 can have a final stop length 112.

[0081] The first and second setting positions 98 and 106 can lead to thefirst and second necks 100 and 108, respectively, with a ramp angle 114.The stop position 110 and the second setting position 106 can lead tothe second 108 and first necks 100, respectively, with a stop angle 116.

[0082]FIG. 24 illustrates narrowing oval or teardrop-shaped receivingelements 32 and 34. FIG. 25 illustrates rectangular receiving elements32 and 34.

[0083]FIG. 26 illustrates the receiving element 32 that can be in theshape of a collar or sleeve. The receiving element 32 can be attached bya connection zone 118 to a rod (not shown) extending from the wall 4 orto the wall 4 itself. The receiving element 32 can have first wedges 120and second wedges 122. The length between the closest point of the firstwedges 120 or of the second wedges 122 can be the neck width 104. Thewedges 120 and 122 can revolve around the entire receiving element 32,thereby forming a single, circular first wedge 120 and a single,circular second wedge 122 (when seen in three-dimensions).

[0084] A receiving element shaftway 124 can be open at one end of thereceiving element 32. The receiving element 32 can have a firstnarrowing 126 near the connection zone 118 and a second narrowing 128near the receiving element shaftway 124. FIG. 27 illustrates thereceiving element 32 that can have the wedges 120 and 122 shaped asscales or stop tabs.

[0085] A length of the wall 4 that can have protrusions 26 and 28 isillustrated in FIG. 28. The protrusions 26 and 28, shown alone invarious embodiments in FIGS. 29 and 25, can be made from an extension130 and a cuff 132. The extension 130 can be shaped cylindrically or, asshown in FIG. 30, as a shaft with a triangular cross-section. Theextension 130 can have an extension height 134 and an extension width136. The extension height 134 can be from about 0.51 mm (0.020 in.) toabout 2.54 mm (0.100 in.), for example about 1.3 mm (0.050 in.). Thefinal stop length 112 can be from about the extension width 136 to about10 mm (0.4 in.), for example about 6.3 mm (0.25 in.).

[0086] The cuff 132 can be shaped as a circle or a square and can besubstantially flat in depth. The cuff 132 can have a cuff height 138 anda cuff width 140. The cuff height 138 can be from about the fixturingdevice connector height 92 to about 5.08 mm (0.200 in.), for exampleabout 2.0 mm (0.080 in). The cuff width 140 can be within the range forthe cuff height 138, above.

[0087]FIG. 31 illustrates a length of the wall 4 having the protrusions26 and 28 formed from tabs cut out of the wall 4. Cut holes 142 canexist in the wall 4 where the material in the protrusions 26 and 28 waslocated in the wall 4 before being cut out.

[0088]FIG. 32 illustrates a length of the wall 4 that can have a firstset and a second set of protrusions 26 and 28 extending from the wall 4.The wall 4 can have a wall radius of curvature 144. The protrusions 26and 28 can have protrusion radii of curvature 146. The protrusion radiiof curvature 146 can be from about the wall radius of curvature 144 toinfinity.

[0089]FIG. 33 illustrates a length of the wall 4 that can have anengagement element 148. The engagement element 148 can be shaped as alip and wrapped around the protrusion 26. The engagement element 148 canenable the first prosthesis 2 to self-engage the second prosthesis 68.For example, the engagement element 148 can snap-fit to the secondprosthesis 68.

[0090]FIG. 34 illustrates the first terminal end 8 and the secondterminal end 10. The second terminal end 10 can have a first guide 150and a second guide 152 that can wrap around the leading edge 20 and thetrailing edge 22, respectively, of the first terminal end 8. The firstterminal end 8 can slide angularly, with respect to the longitudinalaxis 6, within the guides 150 and 152. The guides 150 and 152 can alsominimize the risk of the first terminal end 8 moving too far away fromor becoming misaligned from the second terminal end 10.

[0091] FIGS. 35-43 illustrate embodiments of the first prosthesis 2 at alatitudinal cross-section. The latitudinal cross-section can be across-section parallel with the longitudinal axis 6. FIG. 35 illustratesan embodiment with the wall 4 having a corrugated latitudinalcross-section. FIG. 36 illustrates an embodiment with the wall 4 havinga straight latitudinal cross-section, parallel with the longitudinalaxis 6.

[0092]FIG. 37 illustrates an embodiment having the trailing edge 22angled toward the longitudinal axis 6 at the wall angle 56. FIG. 38illustrates an embodiment having the trailing edge 22 angled away fromthe longitudinal axis 6 at the wall angle 56.

[0093]FIG. 39 illustrates an embodiment having a wall 4 convex towardthe longitudinal axis 6. The wall 4 can be straight or have a lateralconvex radius of curvature 154. FIG. 40 illustrates an embodiment havinga wall 4 concave toward the longitudinal axis 6. The wall 4 can have alateral concave radius of curvature 156 within the same range as thelateral convex radius of curvature 154.

[0094]FIG. 41 illustrates an embodiment having a wall 4 with a topsegment 60, a middle segment 158 and a bottom segment 58. The topsegment 60 and leading edge 20 can be angled away from the longitudinalaxis 6. The bottom segment 58 and trailing edge 22 can be angled awayfrom the longitudinal axis 6. The middle segment 158 can remain parallelto the longitudinal axis 6.

[0095]FIG. 42 illustrates an embodiment having the top segment 60 andthe leading edge 20 that can be angled toward the longitudinal axis 6.The bottom segment 58 and trailing edge 22 can also be angled toward thelongitudinal axis 6. The middle segment 158 can remain parallel to thelongitudinal axis 6.

[0096]FIGS. 43 and 44 illustrate an embodiment of the wall 4 that canhave a bottom segment 58 that can extend from the wall 4 at a retainerangle 160 with respect to the longitudinal axis 6 from about 0° to about90°, more narrowly from about 10° to about 50°, for example about 30°.The bottom segment 58 can also have cuts 162, shown in FIG. 44. The cuts162 can minimize stresses when the bottom segment 58 fans away from themiddle segment 158. The bottom segment 58 can also act as a retentionelement, extending beyond the typical trailing edge 22 and stabilizingthe first prosthesis 2 after the first prosthesis 2 is implanted.

[0097]FIG. 45 illustrates a cross-section of the wall 4 that can have afabric covering 164, for example polyester (e.g., DACRON® from E. I. duPont de Nemours and Company, Wilmington, Del.), polypropylene, PTFE,ePTFE, nylon, extruded collagen, silicone or combinations thereof. Thefabric can be attached to the wall 4 at a first attachment point 166 anda second attachment point 168. The bare area of the wall between theattachment points 166 and 168 can be the engagement surface 170. Thesecond prosthesis 68 can engage the first prosthesis 2 at the engagementsurface 170.

[0098]FIG. 46 illustrates a cross-section of the wall 4 covered entirelyby the covering 164. The second prosthesis 68 can also engage the firstprosthesis 2 at the engagement surface 170 covered by the covering 164.

[0099]FIG. 47 illustrates a length of wall 4 with the engagement element148, shaped as an open lip, on the leading edge 20. The engagementelement 148 can be turned toward the longitudinal axis 6 and toward thetrailing edge 22. FIG. 48 illustrates the engagement element 148 turnedaway from the longitudinal axis 6 and toward the trailing edge 22.

[0100]FIGS. 49 and 50 illustrate an embodiment of the first prosthesis 2that can have a first length 172, a second length 174 and a third length176. The lengths 172, 174 and 176 can be separated by cuts 162 in thewall 4. The engagement element 148 on the first length 172 and thirdlength 176 can turn toward the longitudinal axis 6. The top and middlesegments 60 and 158 of the first length 172 and the third length 176 canbe bent away from the bottom segment 58 as shown by the arrows in FIG.50. The top and middle segments 60 and 158 of the second length 174 canbe similarly bent but in the opposite direction to the top and middlesegments 60 and 158 of the first and third lengths 172 and 176. Theengagement element 148 on the second length 174 can turn away from thelongitudinal axis 6. A lip length 178 can be the length between a firstlip edge 180 of the engagement element 148 on the first length 172 orthird length 176 and a second lip edge 182 of the engagement element 148on the second length 174. The lip length 178 can be small enough to forma seam, crease or seat 184 to aid in seating, receiving and engaging asecond prosthesis.

[0101]FIG. 51 illustrates a length of the wall 4 that can have thelengths 172, 174 and 176. The engagement elements 148 on the firstlength 172 and third length 176 can turn away from the longitudinal axis6. The engagement element 148 on the second length 174 can turn towardthe longitudinal axis 6. The engagement element 148 can then engage asecond prosthesis on both sides of the wall 4.

[0102]FIG. 52 illustrates an embodiment that can have springs 186. Onesegment of each spring 186 can be a latch 188. The springs 186 can havewindings 190 around a rail 192 fixed under the engagement element 148.The springs 186 can also have retaining legs 194 pressed against thewall 4. The latches 188 can be biased to contract, as shown by arrows196, against the wall 4. The latches 188 can be held in the uncontractedposition shown in FIG. 52 by interference beams 198. The interferencebeams 198 can be directly or indirectly rigidly attached to each otherat a proximal end (in the direction of arrows 200) to minimize theinterference beams 198 from deflecting under the force, shown by arrows196, from the latches 188. The interference beams 198 can be removed, asshown by arrows 200, allowing the latches 188 to contract, as shown byarrows 196, against, for example, the second prosthesis, once the secondprosthesis is positioned within the reach of the latches 188.

Method of Making

[0103] The wall 4 can be made from methods known to one having ordinaryskill in the art. For example, the wall 4 can be molded or machined. Theengagement element 148, the corrugation and any other bends in the wall4 can be formed (e.g., pressure formed), molded or machined into thewall 4 or bent into the metal with methods known to one having ordinaryskill in the art.

[0104] The protrusions 26 and 28 and the receiving elements 32 and 34(e.g., at the connection zone 118) can be fixed to the to the wall 4 orformed of the wall 4 by crimping, stamping, melting, screwing, gluing,welding, die cutting, laser cutting, electrical discharge machining(EDM) or a combination thereof. Cuts 162 and holes in the wall 4 can bemade by die cutting, lasers or EDM.

[0105] Any part of the first prosthesis 2, or the first prosthesis 2 asa whole after assembly, can be coated by dip-coating or spray-coatingmethods known to one having ordinary skill in the art. One example of amethod used to coat a medical device for vascular use is provided inU.S. Pat. No. 6,358,556 by Ding et al. and hereby incorporated byreference in its entirety. Time release coating methods known to onehaving ordinary skill in the art can also be used to delay the releaseof an agent in the coating. The coatings can be thrombogenic oranti-thrombogenic. For example, coatings on the inside of the firstprosthesis 2, the side facing the longitudinal axis 6, can beanti-thrombogenic, and coatings on the outside of the first prosthesis,the side facing away from the longitudinal axis 6, can be thrombogenic.

[0106] The first prosthesis 2 can be covered with a fabric, for examplepolyester (e.g., DACRON® from E. I. du Pont de Nemours and Company,Wilmington, Del.), polypropylene, PTFE, ePTFE, nylon, extruded collagen,silicone or combinations thereof. Methods of covering an implantabledevice with fabric are known to those having ordinary skill in the art.

Method of Use

[0107] The first prosthesis 2 can be introduced in an unexpanded stateto an antechamber 202 adjacent to a targeted valve annulus 204 bymethods known to one having ordinary skill in the art. FIG. 53illustrates positioning and lowering, as shown by the arrows, the firstprosthesis 2 to the annulus 204. Because of the collapsible andexpandable nature of the first prosthesis 2, the procedure of implantingthe first prosthesis 2 can be accomplished thorascopically,endoscopically and/or endoluminally. The first prosthesis 2 can beplaced accurately enough into the annulus 204 so that the firstprosthesis 2 does not block vessel openings in chambers neighboring theannulus 204 (e.g., the openings for the coronary vessels) and does notfall out of the annulus 204 (e.g., into a chamber of the heart, aventricle for example). The annulus 204 can have an initial annulusdiameter 206. FIG. 54 illustrates positioning and seating the firstprosthesis 2.

[0108] When the first prosthesis 2 is completely unexpanded, theprotrusion 26 and the receiving element 32 can be aligned as illustratedin FIGS. 55 and 56. As shown in FIG. 55, the extension 130 can belocated in the first setting position 98. As shown in FIG. 56, the ball50 can be located in the first setting position 98.

[0109] The first prosthesis 2 can be circumferentially expanded, asillustrated by the arrows in FIG. 57. The prosthesis can have anexpanded annulus diameter 208. The expanded annulus diameter 208 can befrom about 5 mm (0.2 in.) to about 40 mm (1.6 in.), depends on the sizeof the initial annulus diameter 206, and can be influenced by otheranatomy, anomalies (e.g., narrowing, stenosis) and age (e.g., pediatricsizing). An expansion tool 210 can be used to expand the firstprosthesis 2. Examples of the expansion tool 210 include a balloon, backsides of a clamp jaws, or a flexible plug assembly as shown in FIGS.58-61. Another example of the expansion tool 210 is disclosed in U.S.Pat. No. 5,984,959 to Robertson et al. which is herein incorporated byreference in its entirety.

[0110]FIG. 58 illustrates a flexible plug 212 that can be cylindricaland have a static plate 214 on a first side 216. The plug 212 can bemade from polymers, for example polyurethane or silicone. The plug 212can have a hole 218 in the center of the plug 212. A rigid inner tube220 can pass through the hole 218 and be tied into a knot or pullagainst a washer 222 on the first side 216. A squeeze plate 224 can befixedly attached to an end of a rigid outer tube 226. The outer tube 226can be larger than the inner tube 220, and the inner tube 220 can slidethrough the outer tube 226. A force in the direction of the plug 212 canbe applied to the outer tube 226, as shown by arrows 228. A force in thedirection away from the plug 212 can be applied to the inner tube 220,as shown by arrows 230. The plug can have a resting diameter 232 when noforces are applied.

[0111] Once the forces shown by the arrows 228 and 230 are applied tothe plug 212, the plug 212 can deform away from the tubes 220 and 226,as shown by arrows 234 and illustrated in FIG. 59. Once deformed, theplug 212 can have an expanded diameter 236. The resting diameter 232 andthe expanded diameter 236 can be sized appropriately to the dimensionsof the first prosthesis 2. The deformation of the plug 212 can alsocreate forces in the same direction as the arrows 234. When the forcesshown by the arrows 228 and 230 are removed, the plug 212 can return tothe shape shown in FIG. 58.

[0112]FIG. 60 illustrates another embodiment of the plug 212. The plug212 can have a recessed top surface 238 and a recessed bottom surface240. A top perimeter 242 and a bottom perimeter 244 can be angled fromthe recessed surfaces 238 and 240 to meet a wall 246 of the plug 212.The squeeze plate 224 and the static plate 214 can both be conically orpartially conically shaped to fit the perimeters 242 and 244 of the plug212. As shown in FIG. 61, when the forces shown by the arrows 228 and230 are applied, the plug wall 246 can expand radially and maintain aflat surface.

[0113] When the first prosthesis 2 is completely expanded, theprotrusion 26 and the receiving element 32 can be aligned as illustratedin FIGS. 62 and 63. As shown in FIG. 62, the extension 130 can belocated in the final stop position 110. As shown in FIG. 63, the ball 50can be located in the final stop position 110. The interference fitcaused by the stop angle 116 and neck width 104 of the second neck 108can prevent the protrusion 26 from re-entering the second settingposition 106. In addition, when expanded the first prosthesisfrictionally engages the annulus, expanding the annulus diameter. Whenexpanded, the first prosthesis 2 can also trap vascular plaque betweenthe wall 4 and the perimeter of the annulus 204. The first prosthesis 2can also be partially expanded, forcing the protrusion 26 into thesecond setting position 106.

[0114] Fixturing devices 248 can be used to fix the first prosthesis 2through the fixturing device connectors 88 to the biological mass of theannulus 204, as shown in FIG. 64. Examples of fixturing devices 88 aresutures, clips, staples, pins and combinations thereof.

[0115] FIGS. 65-68 illustrate one embodiment of a method of fixing thefirst prosthesis 2 to the annulus 204. FIG. 65 illustrates an embodimentof a fixturing device assembly 250. The fixturing device assembly 250can have a needle 252. The needle 252 can be curved or have a curvedtip. The needle 252 can also be attached at a proximal end to a distalend of a line 254. The proximal end of the needle 252 can also beattached directly to the can 256 without the line 254 or formed as thecan 256. A proximal end of the line 254 can be attached to a can 256.The can 256 can be a flexible cylindrical storage device, for example acoil. The can 256 can removably hold the fixturing device 148. Thefixturing device 148 can have a fixturing element 258, for example awire or fiber. The fixturing element 258 can have a ball 260 at a firstend and a radially expandable portion 262 at a second end. The fixturingdevice 248 can also have a pledget 264 on the fixturing element 258between the ball 260 and the expandable portion 262.

[0116] The fixturing device assembly 250 can be positioned so the needle252 is adjacent to the fixturing device connector 88, as shown by arrows266. The needle 252 can then be pushed through the fixturing deviceconnector 88 and the annulus 204, as shown by arrow 268 in FIG. 66. Theneedle 252 can then be pulled away from the annulus 204, as shown byarrow 270 in FIG. 67. The can 256 can follow the path of the needle 252through the annulus 204, as shown by arrow 272. The pledget 264 can alsobe larger than the fixturing device connector 88, and the pledget 264can provide an interference fit against the fixturing device connector88. The needle 252 can continue to be pulled away from the annulus 204,pulling the can 256 out of the annulus 204, as shown by arrow 274 inFIG. 68. The interference fit of the pledget 264 against the fixturingdevice connector 88 can provide a resistive force holding the fixturingdevice 248 and causing the fixturing element 258 to slide out of the can256 as the needle 252 is pulled away from the annulus 204. The radiallyexpandable portion 262 can then radially expand, thereby causing thefirst prosthesis 2 and the annulus 204 to be fixed between the pledget264 and the radially expandable portion 262.

[0117] The inner surface of the can 256 can be designed—for example bycoiling, corrugation, or other roughening—to adjust the friction betweenthe inner surface of the can 256 and the fixturing device 148. Thisfriction can influence the amount of resistive force necessary to removethe fixturing device 148 from the can 256. The resistive force can belarger than about the force necessary to have the fixturing device 148fall out of the can 256 before the fixturing device 148 has passedthrough the annulus 104. The resistive force can also be less than aboutthe force necessary to deform the pledget 264 sufficient to pull thepledget 256 through the fixturing device connector 88. The resisticeforce can be, for example, about 1.1 N (0.25 lbs.).

[0118] A second prosthesis 68 can then be positioned on the engagementelement 148, as shown by the arrows in FIG. 69. Once seated on theengagement element 148, the second prosthesis 68 can then be engaged bythe first prosthesis 2, as shown in FIG. 70. Examples of secondprostheses 68 include a connection adapter and a heart valve crown withleaflets 276, for example, U.S. Pat. No. 6,371,983 to Lane which isherein incorporated by reference in its entirety.

[0119]FIG. 71 illustrates another embodiment of the heart valve assembly278 with the second prosthesis 68. The first prosthesis 2 can have atapered wall 280 to provide a longitudinal stop and to guide insertionof the second prosthesis 68 into the first prosthesis 2, as shown byarrows 282. The tapered wall 280 can also push back the annulus 204,maintaining the expanded annulus diameter 208 when the second prosthesis68 is engaged in the first prosthesis 2. The second prosthesis 68 canhave spring lock tabs 284 to fix to the engagement element 148. Thespring lock tabs 284 can angle outwardly from the longitudinal axis 6.The first and second prostheses 2 and 68 can have first and secondprosthesis diameters 288 and 290, respectively. The first prosthesisdiameter 288 can be larger than the second prosthesis diameter 290. FIG.72 illustrates the embodiment of the heart valve assembly 278 of FIG.71, however the second prosthesis diameter 290 can be larger than thefirst prosthesis diameter 288, and the spring lock tabs 284 can angleinwardly toward the longitudinal axis 6. The first prosthesis 2 and thesecond prosthesis 68 act to maintain the expanded annular lumen diameter208.

[0120]FIG. 73 illustrates another embodiment of the heart valve assembly278 with a second prosthesis 68 that can have fixation points 286 thatalign with fixation points 286 on the first prosthesis 2 to allowinsertion of sutures, grommets, clips 292 or pins 294 through thealigned fixation points 286 to fix the first prosthesis 2 to the secondprosthesis 68.

[0121]FIG. 74 illustrates another embodiment of the heart valve assembly278 with a multi-lobed stiffening ring 296 that can be placed near theedge of the second prosthesis 68 as shown by arrows 298. The secondprosthesis 68 can have several flaps 300. The flaps 300 can wrap aroundthe stiffening ring 296, as shown by arrows 302. The wrapped stiffeningring 296 can increase the rigidity of the second prosthesis 68 and canengage the engagement element 148.

[0122]FIG. 75 illustrates yet another embodiment of the heart valveassembly 278 with an embodiment of the first prosthesis 2 equivalent tothe embodiment in FIG. 52. The second prosthesis 68 can have latchopenings 304 to receive the latches 188. When the second prosthesis 68is lowered into the first prosthesis 2, the interference beams 198 canbe removed, as shown by arrows 200. The latches 188 can then contractonto the latch openings 304.

[0123]FIG. 76 illustrates an embodiment of the heart valve assembly 278with an embodiment of the first prosthesis 2 equivalent to theembodiment in FIGS. 11 and 12. The second prosthesis can have a rib 306to fit within the groove 64. The second prosthesis 68 can also have anupper arm 308 that can have a top magnet 70 and a lower arm 310 that canhave a bottom magnet 72. The magnets 70 and 72 in the second prosthesis68 can have polarities opposite of the polarities of the correspondingmagnets 70 and 72 in the first prosthesis 2. FIG. 77 illustrates anembodiment of the heart valve assembly 278 with an embodiment of thefirst prosthesis equivalent to the embodiment in FIGS. 13 and 14.

[0124]FIG. 78 illustrates an embodiment of the heart valve assembly 278with an adapter 312 connecting the second prosthesis 68 to the firstprosthesis 2. The adapter 312 can have spring lock tabs 284 to fix tothe engagement element 148, and the adapter 312 can have a stop ridge314 to position the adapter 312 against the wall 4.

[0125] The adapter 312 can also have fixation points 286 that align withother fixation points 286 on the second prosthesis 68 to allow insertionof sutures, grommets, clips, pins, or the fixturing devices 248, throughthe aligned fixation points 286 to fix the adapter 312 to the secondprosthesis 68. The second prosthesis 68 can also be lowered into the topof the adapter 312 as shown by arrow 316. The adapter 312 can attach tothe inside or outside of the first or second prosthesis 2 or 68depending on the dimensions and the orientation of the attachmentapparatus (e.g., unidirectional clips).

[0126] The adapter 312 can also have multiple shapes of cross-sections,as shown in FIGS. 79 and 80. As shown in FIG. 79, cross-section C-C canhave three lobes 318 and three scallops 320. One scallop 320 can bebetween each lobe 318. Cross-section C-C can be the same as thecross-section of the second prosthesis 68 where the second prosthesis 68engages the adapter 312. As shown in FIG. 80, cross-section D-D can becircular. Cross-section D-D can be the same as the cross-section of thefirst prosthesis 2 where the first prosthesis 2 engages the adapter 312.

[0127]FIG. 81 illustrates a second prosthesis 68 received by a firstprosthesis 2. The second prosthesis 68 can have three lobes 318. Thesecond prosthesis can have a scallop 320 between each two lobes 318. Thescallop gap 322 between each scallop 320 and the wall 4 can be coveredby a fabric during use of the prostheses 2 and 68.

[0128]FIG. 82 illustrates that a lever device 324, for example a clampor scissors, can be forced, as shown by arrows, into the scallop gap322. As illustrated in FIG. 83, once legs 326 of the lever device 324are placed next to two scallops 320, the lever device 324 can besqueezed, as shown by arrows, thereby crushing the second prosthesis 68and separating it from the first prosthesis 2. As illustrated in FIG.84, the second prosthesis 68 can be removed from the first prosthesis 2,as shown by arrows, once the second prosthesis 68 is separated from thefirst prosthesis 2. Once the second prosthesis 68 is removed, a newsecond prosthesis 68 can be added as described above. Leaflet failurecan be fixed easily and inexpensively by implanting a new secondprosthesis 68. Circumferential expansion of the first prosthesis 2 andreplacement of the second prosthesis 68 to account for pediatricexpansion of the valve can also be performed easily and inexpensively.

[0129] It is apparent to one skilled in the art that various changes andmodifications can be made to this disclosure, and equivalents employed,without departing from the spirit and scope of the invention. Elementsshown with any embodiment are exemplary for the specific embodiment andcan be used on other embodiments within this disclosure.

We claim:
 1. A biologically implantable first prosthesis for a heartvalve comprising: a circumferentially expandable wall, wherein the wallhas a longitudinal axis, and wherein the wall has a latitudinalcross-section perpendicular to the longitudinal axis, and wherein thewall has a longitudinal cross-section parallel to the longitudinal axis,and an engagement element configured to self-engage a second prosthesis.2. The first prosthesis of claim 1, further comprising a stop, whereinthe stop prevents the wall from circumferentially decreasing.
 3. Thefirst prosthesis of claim 2, wherein the stop prevents the wall fromcircumferentially expanding.
 4. The first prosthesis of claim 2, whereinthe wall is resiliently expandable.
 5. The first prosthesis of claim 2,wherein the wall is deformably expandable.
 6. The first prosthesis ofclaim 2, wherein the wall is mechanically expandable.
 7. The firstprosthesis of claim 2, wherein the latitudinal cross-section comprisesan open form.
 8. The first prosthesis of claim 2, wherein thelatitudinal cross-section comprises a spiral.
 9. The first prosthesis ofclaim 2, wherein the wall comprises a first terminal end.
 10. The firstprosthesis of claim 9, wherein the wall comprises a second terminal end.11. The first prosthesis of claim 9, wherein the latitudinalcross-section comprises a spiral.
 12. The first prosthesis of claim 9,further comprising a first protrusion.
 13. The first prosthesis of claim12, wherein the first protrusion is attached to the wall.
 14. The firstprosthesis of claim 13, wherein the first protrusion extends from thewall with a vector having a radial component with respect to thelongitudinal axis.
 15. The first prosthesis of claim 14, wherein thefirst protrusion comprises a dimple.
 16. The first prosthesis of claim15, wherein the first protrusion comprises a tab.
 17. The firstprosthesis of claim 16, further comprising a receiving element.
 18. Thefirst prosthesis of claim 17, wherein the receiving element comprises anelement in the wall.
 19. The first prosthesis of claim 12, wherein thefirst protrusion extends from the wall with a vector having an angularcomponent with respect to the longitudinal axis.
 20. The firstprosthesis of claim 19, wherein the first protrusion comprises a ball.21. The first prosthesis of claim 20, further comprising a receivingelement.
 22. The first prosthesis of claim 21, wherein the receivingelement comprises a collar.
 23. The first prosthesis of claim 9, furthercomprising a receiving element.
 24. The first prosthesis of claim 23,wherein the receiving element is configured to receive a protrusionextending from the wall with a vector with a radial component withrespect to the longitudinal axis.
 25. The first prosthesis of claim 24,wherein the receiving element is configured to receive a protrusionextending from the wall with a vector having an angular component withrespect to the longitudinal axis.
 26. The first prosthesis of claim 12,further comprising a second protrusion.
 27. The first prosthesis ofclaim 26, wherein the first protrusion is located at a first lengthalong the longitudinal axis and wherein the second protrusion is locatedat a second length along the longitudinal axis.
 28. The first prosthesisof claim 26, wherein the first protrusion and the second protrusion arelocated at a first length along the longitudinal axis.
 29. The firstprosthesis of claim 26, wherein the first protrusion comprises a firsttab, and the first prosthesis further comprises a first port in the wallfor receiving the first tab.
 30. The first prosthesis of claim 29,wherein the second protrusion comprises a second tab and a second portin the wall for receiving the second tab.
 31. The first prosthesis ofclaim 29, wherein the second protrusion comprises a ball, and the firstprosthesis further comprises a collar for receiving the ball.
 32. Thefirst prosthesis of claim 1, further comprising a fixturing deviceconnector.
 33. The first prosthesis of claim 32, wherein the fixturingdevice connector comprises a port in the wall.
 34. The first prosthesisof claim 1, wherein the wall is corrugated.
 35. The first prosthesis ofclaim 1, wherein the wall has a leading edge and a trailing edge, andfurther comprising a turned lip on the leading edge.
 36. A heart valveassembly comprising: the first prosthesis of claim 1, and the secondprosthesis received by the first prosthesis.
 37. The assembly of claim36, wherein the second prosthesis is a crown.
 38. The assembly of claim37, wherein the crown is engaged by the engagement element.
 39. Theassembly of claim 37, wherein the crown comprises a leaflet.
 40. Theassembly of claim 36, wherein the first prosthesis is a ring.
 41. Theassembly of claim 36, wherein the second prosthesis is fixedly connectedto the first prosthesis.
 42. The assembly of claim 36, wherein thesecond prosthesis is removably connected to the first prosthesis. 43.The assembly of claim 36, wherein the second prosthesis is snap-fittedto the first prosthesis.
 44. A biologically implantable prostheticassembly for a heart valve comprising: the first prosthesis of claim 32,and a fixturing device attached to the fixturing device connector,wherein the fixturing device fixes the first prosthesis to a biologicalmass.
 45. The assembly of claim 44, wherein the fixturing devicecomprises a suture.
 46. The assembly of claim 44, wherein the fixturingdevice comprises a clip.
 47. The assembly of claim 44, wherein thefixturing device comprises a staple.
 48. The assembly of claim 44,wherein the fixturing device comprises a pin.
 49. The assembly of claim44, wherein the fixturing device comprises a radially expandable wire.50. A biologically implantable first prosthesis for a heart valvecomprising: a wall comprising a first edge and a second edge, whereinthe wall has a longitudinal axis at the center of the first prosthesis,and wherein at least a portion of the wall is angled away from or towardthe longitudinal axis, and wherein the first edge comprises anengagement element for engaging a second prosthesis.
 51. The firstprosthesis of claim 50, wherein the engagement element is turned towardthe second edge.
 52. The first prosthesis of claim 50, wherein the firstedge is the leading edge.
 53. The first prosthesis of claim 50, whereinthe engagement element is turned toward the longitudinal axis.
 54. Thefirst prosthesis of claim 50, wherein the engagement element is turnedaway from the longitudinal axis.
 55. The first prosthesis of claim 50,wherein the engagement element comprises a first segment and a secondsegment, and wherein the first segment is turned away from thelongitudinal axis and the second segment is turned toward thelongitudinal axis.
 56. The first prosthesis of claim 50, furthercomprising a fixturing device connector.
 57. The first prosthesis ofclaim 56, wherein the fixturing device connector comprises a port in thewall.
 58. The first prosthesis of claim 50, wherein the wall iscorrugated.
 59. The first prosthesis of claim 50, wherein thelongitudinal cross-section comprises a convex curve with respect to thelongitudinal axis.
 60. The first prosthesis of claim 50, wherein thelongitudinal cross-section is a convex curve with respect to thelongitudinal axis.
 61. The first prosthesis of claim 50, wherein thewall is circumferentially expandable.
 62. A heart valve assemblycomprising: the first prosthesis of claim 50, and the second prosthesis,wherein the second prosthesis is connected to the engagement element.63. The assembly of claim 62, wherein the second prosthesis is a crown.64. The assembly of claim 63, wherein the crown is engaged by theengagement element.
 65. The assembly of claim 63, wherein the crowncomprises a leaflet.
 66. The assembly of claim 62, wherein the firstprosthesis is a ring.
 67. The assembly of claim 62, wherein the secondprosthesis is fixedly connected to the first prosthesis.
 68. Theassembly of claim 62, wherein the second prosthesis is removablyconnected to the first prosthesis.
 69. The assembly of claim 62, whereinthe second prosthesis self-enagages to the first prosthesis.
 70. A heartvalve assembly comprising: a first prosthesis; a first magnet in thefirst prosthesis; a second prosthesis; and a second magnet in the secondprosthesis, wherein an attraction between the first magnet and thesecond magnet engages the first prosthesis to the second prosthesis. 71.A method of implanting a heart valve in a valve annulus comprising:attaching a first prosthesis to the valve annulus, the first prosthesiscomprising a circumferentially expandable wall, wherein the wall has alongitudinal axis, and wherein the wall has a latitudinal cross-sectionperpendicular to the longitudinal axis, and self-attaching a secondprosthesis to the first prosthesis.
 72. The method of claim 71, whereinthe first prosthesis is a ring.
 73. The method of claim 71, wherein thesecond prosthesis is a crown.
 74. The method of claim 71, wherein thewall comprises a first terminal end.
 75. The method of claim 74, whereinthe wall comprises a second terminal end.
 76. The method of claim 71,wherein the latitudinal cross-section comprises a spiral.
 77. The methodof claim 71, wherein attaching the first prosthesis comprisespositioning the first prosthesis in the annulus and circumferentiallyexpanding the first prosthesis.
 78. The method of claim 71, whereinattaching the first prosthesis comprises fixing the first prosthesis toa biological mass with a fixturing device.
 79. The method of claim 71,wherein attaching the first prosthesis comprises positioning the firstprosthesis in the annulus.
 80. The method of claim 71, wherein attachingthe first prosthesis comprises snap-fitting the second prosthesis to thefirst prosthesis.
 81. The method of claim 71, further comprisingremoving the second prosthesis.
 82. A method of removing changing aheart valve comprising removing a second prosthesis from a firstprosthesis, wherein the first prosthesis is the first prosthesis ofclaim
 1. 83. The method of claim 82, further comprising replacing thesecond prosthesis with another prosthesis.
 84. A method of implanting aheart valve in a valve annulus comprising: attaching a first prosthesisto the valve annulus, the first prosthesis comprising a wall, whereinthe wall comprises a first edge and a second edge, and wherein the wallhas a longitudinal axis, and wherein at least a portion of the wall isangled away from or toward the longitudinal axis, and wherein the firstedge comprises an engagement element, and attaching a second prosthesisto the first prosthesis.
 85. The method of claim 84, wherein theengagement element is turned away from the longitudinal axis.
 86. Themethod of claim 85, wherein the first prosthesis is a ring.
 87. Themethod of claim 86, wherein the second prosthesis is a crown.
 88. Themethod of claim 87, wherein the first edge is the leading edge and thesecond edge is the trailing edge.
 89. The method of claim 88, whereinattaching the crown comprises snap-fitting the crown to the firstprosthesis.
 90. The method of claim 89, wherein the second edgecomprises a retention element.
 91. A method of increasing andmaintaining the size of a biological valve annulus comprising: placing acircumferentially expandable first prosthesis in the annulus,circumferentially expanding the first prosthesis to an expanded size,and circumferentially maintaining the first prosthesis at the expandedsize.
 92. The method of claim 91, wherein circumferentially expandingcomprises increasing the radius of the annulus from about 0.1 mm toabout 2.0 mm.
 93. The method of claim 91, wherein the first prosthesiscomprises an engagement element configured to receive a secondprosthesis.
 94. A method of fixing a heart valve assembly to abiological mass comprising: positioning the assembly near the mass,inserting a fixation device through the assembly and the mass, whereinthe fixation device comprises a first end, a second end, and a middle,and wherein the first end is expandable, and wherein the first end andthe second end are on opposite sides of the assembly and the mass, andexpanding the first end.